Technology allows files to be stored under certain file names in Windows

The U.S. Patent and Trademark Office has upheld two Microsoft Corp. patents for technology that controls how files are stored in the Windows operating system, according to a Microsoft spokeswoman.

The patent office ruled yesterday that patents that cover the File Allocation Table (FAT) file naming system in Windows are valid after completing a re-examination of the patents at the request of both a public interest group and an individual, said Tricia Payer, a spokeswoman for Microsoft's public relations firm, Waggener Edstrom Inc.

Payer said Microsoft received notices this week that the patent office was terminating its re-examination of the patents, Nos. 5,579,517 and 5,758,352, and issuing updated patent certificates for the original patents. The patents cover the ability to handle long and short filenames.

FAT is the technology in Windows that allows files to be stored under certain file names, but it is not exclusive to Windows. FAT also is widely used in removable media such as Universal Serial Bus memory sticks and cameras.

Microsoft claims that it developed FAT in 1976 and was granted a patent on the file system in 1996. But some in the industry, particularly those with interests in developing and promoting open-source software, have disputed the FAT patents Microsoft holds.

Microsoft licenses FAT to third parties, who must pay the software company to use it in their technology, Payer said.

"We still believe these patents are invalid and that a process that gave the public equal time to present its positions would result in them being found as such," said Daniel Ravicher, executive director of the Pubpat.

Pubpat made its request in April 2004, and Hoffman made his in January 2005, according to patent documents.

The patent office initially rejected patent 5,579,517 in September 2004 after a re-examination, but Microsoft submitted more materials to support its claim.

The decision is the patent office's final decision, according to agency documents.

Eben Moglen, a Columbia University law professor and general counsel for the Free Software Foundation, said patent re-examination, in general, is weighted in favor of patent holders because they can provide evidence to support patents to the patent office without public recourse.

"I would point out that patent re-examination in the United States is an 'ex parte' process, in which the patent holder has an unfair opportunity to communicate its supposed evidence in support of its patent to the Patent and Trademark Office without any cross-examination, review, challenge or other procedural right for the party seeking reexamination," he said. "Even the petitioner's knowledge about the patent holder's statements and evidence is limited to a terse summary provided by the patent examiner. This system is uniquely fraught with possibilities for abuse, a problem exacerbated by the patent office's recent decision to use a new 'streamlined' internal procedure for appeals like that brought by Microsoft for the reinstatement of its patent."